Tomas (your music is great btw), I think their music is such that it doesn't matter to a huge degree how they look when they play it live. It's a little different IMO from guys about to turn 70 who are still playing the same rock 'n roll hits from 50 years ago and bouncing around on stage.
They've both made a lot of relevant music since the 80's and 90's in their respective solo albums, collaborations and so on, so it's hard for me to begrudge them a reunion disc and tour, as this is most likely just that. You're probably right they're doing this for the same reason every other band from previous decades with previous fame reunites.
I don't think it'll hurt their cult status though, the fact that they're gonna sell a ton of music and concerts without essentially changing themselves or their sound tells me that. They'd have to become skinhead nazis (Lisa Gerrard- highly suspect
) and sing only Britney Spears covers in order to ruin the nostalgia.
Listening to a few of their new songs on youtube, I'm impressed that the quality is still good- Brendan's range has narrowed a tad but he can still croon, baby, and Lisa Gerrard can basically phone in those angelic notes without much problem. The songwriting is pretty solid. I'm not sure how relevant an album it is, in terms of their legacy, but at least they reunited with an actual album of quality music. It's not bad music, regardless of whether I'd prefer a different direction.
Tomas I'd agree that if they that just tour and keep singing their old classics indefinitely until there are no more crowds, it would hurt their rep... I just don't see that happening though. There is one great song so far I've heard which is Children of the Sun. This could have easily been the last song on the album (it was the first), a fitting and gracious goodbye, I mean that in the best sense.